


Full of Grace

by ami_ven



Category: Supernatural
Genre: Angelic Lore, Castiel's Angelic Grace (Supernatural), Descriptions of sex, Established Relationship, M/M, POV Sam Winchester, but no actual sex
Language: English
Status: Completed
Published: 2019-11-04
Updated: 2019-11-04
Packaged: 2021-01-22 19:56:17
Rating: Teen And Up Audiences
Warnings: No Archive Warnings Apply
Chapters: 1
Words: 3,152
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/21307718
Author URL: https://archiveofourown.org/users/ami_ven/pseuds/ami_ven
Summary: There’s something going on with Dean, but it isn’t exactly what Sam thinks.
Relationships: Castiel & Sam Winchester, Castiel/Dean Winchester, Dean Winchester & Sam Winchester
Comments: 8
Kudos: 61





	Full of Grace

Sam yawned as he rolled out of bed, but it turned into a groan by the time his feet hit the floor.

Their hunt the night before had been a fairly standard salt-and-burn, but the ghost had particularly enjoyed throwing both him and Dean into the basement walls while they’d worked to dig out enough of the body to torch. Fortunately, he’d only been able to throw them around one at a time, so there’d been more chances to dig, but both parts of that had left Sam with very sore muscles.

He wasn’t actually injured, though, so he counted it as a win and headed to the kitchen for a cup of coffee and a heating pad.

The smell of frying bacon took Sam a moment to process, so he was surprised to enter the room and find his brother at the stove, humming to himself as he stirred a pan of eggs.

“Mornin’, Sammy.”

“Dude, what the hell?” asked Sam. He found the heating pad in one of the cabinets and threw it in the microwave. “How are you not in serious pain right now?”

“What?” asked Dean. “From that weak-ass ghost?”

“That ‘weak-ass’ ghost threw me into a wall seven times, Dean. And it threw you _nine_, because you can’t keep your mouth shut.”

“I really can’t,” his brother agreed, grinning. “You want cheese in your eggs?”

“Sure,” said Sam, then frowned. “So why aren’t you feeling at least as bad as I am?”

“Clean living?”

“Dean…”

“Look, I don’t know,” said Dean. “Maybe you got hit harder than me, or at a wrong angle, or something.”

“Maybe,” said Sam, but he didn’t think that was it.

Dean scooped the eggs and bacon onto a large serving plate and set them on the table. “Maybe you’re just getting old, Sammy.”

“I’m four years younger than you!” his brother protested.

“Yeah, but you’re freakishly tall. Didn’t Andre the Giant die from being so big?”

Sam scowled. “I’m only slightly above average height,” he said, as the microwave beeped. He pulled out the heating pad and sighed in relief as he settled it on his aching shoulder.

“Still, more surface area,” Dean argued, around a mouthful of eggs. “That’s a pretty good hickey you got going there.”

“I was thrown into a support beam by a dead, pissed-off, middle-aged salesman,” Sam grumbled, and pulled three more pieces of bacon onto his plate than he’d planned on eating.

*

They were hunting a wendigo, deep in the woods of Ohio, when Dean stopped short. “Sam.”

“What?” his brother hissed.

“Do you hear that?”

“Uh, _yeah_,” said Sam. They’d been following the howls for the last ten minutes. “It’s a wendigo.”

“No, it’s _two_ wendigos,” whispered Dean. He paused, expectantly, but Sam frowned. “You can’t hear that?”

“Nope.”

“There’s two, man, I’m telling you. One’s more… growly than the other one. A bass and a tenor, you know?”

Sam shook his head. “I can only hear one.”

There _were_ two wendigos, and they were not at all pleased about being interrupted. Sam ended up facing the smaller one, and he was barely holding his own – it must have fed recently, he thought, then confirmed it when he was flung into a bush that also held the tattered and bloodstained orange parka their missing hiker had been wearing.

“Sammy, look out!” yelled Dean, and Sam barely rolled out of the way in time. 

Dean fired at the wendigo, more to distract it than to actually hurt it, not with regular bullets, but it worked well enough as Sam scrambled back to his feet and took the wendigo’s head off.

“Where’s—?” Sam began, but the larger wendigo was already on them, catching Dean in the side with its claws to send him tumbling across the forest floor. He hit the base of the tree, hard, and didn’t get up.

“Dean!” yelled Sam.

He found the shotgun he’d dropped earlier and fired, drawing the wendigo’s attention – but with its attention on him, it would be much harder to kill by himself, especially one as big as this.

“Crap,” muttered Sam, as he backed away quickly. “Crap, crap, crap…”

Just as his back hit a tree, the wendigo froze, wide eyes blazing blue for a moment before it slumped, lifeless, to the ground. Castiel stood where it had just been, the hand he’d used to smite the wendigo falling slowly to his side.

“Sam,” he said. “Are you injured?”

“No, just – Dean!”

Across the clearing, Dean had managed to sit up against the tree trunk, one arm wrapped protectively around his middle, but he waved his free hand lazily at them. “’M fine,” he muttered. “Just go the wind knocked outta me.”

“The wendigo got you, Dean,” protested Sam. “Let me see…”

He started to crouch next to his brother, but winced and straightened quickly enough to overbalance. Cas caught his arm, scowling.

“I should never believe a Winchester if he tells me he’s fine,” the angel grumbled. He unceremoniously pressed two fingers to Sam’s forehead, and Sam felt the pain of his bruised ribs flare for a split-second before it faded entirely.

“Thanks, Cas. But Dean…”

This time, Sam managed to kneel without falling over, and he batted Dean’s hands out of the way to peel up the hem of his t-shirt. “Huh.”

Dean glared at him. “See if I save your ass _next_ time,” he said, which was such an empty threat that Sam ignored him.

It had looked much worse when Dean had been thrown across the clearing, but up close, he could tell that it wasn’t so bad. Dean’s previously-gray t-shirt was nearly soaked through with blood, but the three parallel claw marks were fairly shallow. They would probably have needed only a couple of stitches, if he didn’t have his own personal guardian angel.

“Hardly even hurts,” said Dean.

Cas rolled his eyes, then placed his palm over the Dean’s ribs and used the other to cup Dean’s face.

Sam coughed and pointedly faced the other direction. Cas had wholeheartedly embraced the human idea of ‘kissing it better’ but he and Dean usually got carried away, and that was something a little brother did not need to see.

*

Dean didn’t get sick very often, but when he did, it was usually _epic_. He’d have week-long bouts of the flu, head colds with sneezes that shook the whole building, fevers that brought on full hallucinations – so when Dean turned off a _Dr. Sexy_ marathon to go to bed early, Sam knew something was up.

He did a check of their medicine supplies (surprisingly good, now that they had a permanent address) before he went to bed, and made sure to keep his door open a crack, in case Dean needed anything.

Sam woke later than he intended, to the smell of something delicious coming from the kitchen.

“Dean?” he asked, stopping in the kitchen doorway. 

“Hey, Sammy,” his brother greeted. His voice sounded like he had a stuffy nose, but he was smiling. “Just eggs and bacon this morning. I was gonna make pancakes, but I don’t really feel like it. You want any of that healthy crap, you can make it yourself – I need _protein_ to deal with this cold.”

“Should you even be cooking if you’re sick?” Sam asked.

“What, you afraid of catching something?”

“No. Just seems unsanitary.”

Dean shrugged. “It’s only a cold. I’ll be all stuffed up for a couple of days, then I’ll be fine. And that’s only if Cas doesn’t come home early from Donna’s and heal me. Get some plates, will you?”

“You don’t get sick, Dean,” said Sam, pulling plates out of the cabinet. “Except for when you’re _sick_.”

“In other news, water is wet and the sky is blue.”

“Dean…”

His brother shrugged. “Hey, if you’re so worried about me, _you_ can go on the supply run I had planned and I’ll stay here and rest.”

“Rest?” Sam repeated, skeptically.

Dean grinned. “There’s an old-school _Trek_ marathon today.”

“Of course there is,” said Sam. “And you know what? I will go. I’ll get all kinds of healthy crap, to help you feel better.”

“Whatever, Samantha. Don’t forget the pie.”

*

“Hey, Cas, have you got a minute?” asked Sam.

The angel tilted his head, confused, but followed him away from the kitchen where Dean was still working on dinner, and into the library. “How can I help you, Sam?”

“You would know if something was going on with Dean, right? You’d be able to tell?”

“Your brother and I do share a profound bond,” Cas agreed. “But I prefer not to use by abilities to read his thoughts unless specifically invited.”

“No, that’s fine,” said Sam. “I mean, more physically. Does it seem like Dean is, I don’t know, under the influence of something?”

“You are both warded against demons and angels,” said Cas. “And Dean has not recently been drinking more than is socially acceptable.”

“No, I mean…” Sam ran a frustrated hand through his hair. “He’s been acting weird, okay? It’s not even anything bad, as far as I can tell, but it’s starting to freak me out.”

“What is?” Cas asked.

“He hasn’t been getting hurt as much on jobs, even though he’s taking the same stupid risks as always. And if he does get hurt, it’s never as bad as it looks like it should be.”

“Oh?” said Cas.

“Yeah,” said Sam. “We both get tossed into the same brick wall, and I can feel it for a week, but Dean’s fine by the next day. He’s four years older than me, Cas. And nearly middle-aged.”

“That is true.”

“And he’s… he’s…” Sam continued. “Lately, he seems to know more about a hunt than our research, you know? Like, if there were two wendigos, or how recently a vamp had fed. It’s _weird_, it’s almost like when I…”

Sam trailed off, as something terrible occurred to him. “Cas,” he said, slowly, “you would know if Dean was drinking demon blood, wouldn’t you?”

“I would,” the angel agreed. “And I can assure you that he is not.”

“No, no, of course he’s not,” said Sam, letting out a breath he hadn’t realized he was holding – he hadn’t really believed Dean was, except that he kind of had. “But there is something going on, and you know what it is.”

“Yes,” admitted Cas. “I realized it long before you did, of course. And to be honest, we had hoped that you would not have noticed.”

“Not have noticed—” Sam repeated, then scowled. “_We_?”

“Dean has been aware of this from the beginning,” Cas said, like Sam was an idiot for not knowing that. “He relies on his physical fitness and was very quickly aware of any changes.”

“Then why not tell me?” Sam pressed.

“There was no danger, and nothing you could do to alter the situation,” said Cas. “We felt it would only make you uncomfortable.”

“Actually, _I_ wanted to see his face when he finally figured it out,” said Dean, grinning at them from the kitchen doorway. “And I don’t know what’s got me more disappointed, Sammy, that you think I’d drink demon blood, or that I’d cheat on Cas to do it.”

“I don’t think I really believed either of those things,” said Sam. “But what else was I supposed to think?” He paused, looking between them. “Wait, do angels work the same way? Dean, are you drinking angel blood?”

“Dude, _gross_,” said Dean, at the same time that Cas said, “No one is consuming anyone’s blood.”

“Just checking,” said Sam. “But if it’s not that… what _is_ going on?”

Cas hesitated. “I had no way of knowing the effect that… certain things would have on Dean,” he said, softly. “Other angels have spent more time on Earth, but never in a single vessel, or in the company of just one human. Angelic liaisons with humans were usually brief, even when they resulted in nephilum.”

“The original deadbeat dads,” said Dean. “After Chuck, of course.”

Cas frowned, but didn’t otherwise acknowledge that. “Most of these unions took place in biblical times, when God – and therefore, the angels – took a more active role in human lives. But angels had duties in heaven. If one wanted to stay on Earth, they would have had to Fall, and then would have no grace to share with their paramour.”

“Good thing I’m not one of those, then,” said Dean.

“No,” Cas agreed, solemnly. “You mean a great deal more to me.”

“Cas…” said Dean, ears turning pink.

Sam grinned at his brother’s discomfort, then asked, “So, if it’s your grace, Cas, why aren’t I healing faster, too? You’ve used it on me before.”

Dean’s expression turned gleeful in an instant. “Tell him, Cas,” he said. “Just like you told me. He asked!” he added, when Cas continued to frown.

“Very well. The use of my grace doesn’t usually leave any trace behind,” Cas explained. “When I heal you, Sam, I am merely speeding up the natural process of your body, and that small amount of grace is consumed, the same way your body normally consumes energy from digested food.”

“Okay,” said Sam. “I guess I’d never really thought about how it works, but that makes sense.”

“This vessel, however,” Cas continued, “is almost entirely sustained by my grace. There is grace in every cell, increased by how long I have been in this particular vessel and again because I am now the sole occupant.”

“Okay,” said Sam again, but Dean just grinned.

“C’mon, Cas, the whole thing.”

“Apart from the properties of their blood that we have witnessed, I don’t know much more about the transfer of power from a demonic vessel,” said Cas. “But with angels, any of the bodily fluids can impart grace, of varying levels, when consumed. Saliva is not especially powerful, but can be used to augment healing. Dean much prefers that I use a kiss to heal him when he is injured, rather than merely a touch.”

“Dude,” protested Dean, as though Sam hadn’t seen them making out dozens of times by now.

Cas ignored him. “Tears can also be used for healing,” he continued, “but they are often dependent on the emotion that caused them, which can be difficult to control. The blood of any living creature has power, but angels are unique in that it is important how the blood is obtained – blood _taken_ can often be used to track or even curse those that spill it, while blood _given_ by an angel will make powerful wards and sigils.”

“Right,” said Sam, starting to feel a little overwhelmed by all the information. Cas didn’t talk very often about being an angel, and generally seemed unaware at how little humans knew about them. “Sure, right.”

“Of course,” said Cas, “the fluid which contains the highest concentration of grace and is the most relevant at the present moment is semen, as it is partly responsible for the creation of new life.”

Sam choked on his next breath. “Did you say—? And, wait, _consumed_!?”

Cas frowned, glancing back at Dean, then continued, “For any lasting transfer of grace, it must be ingested. And for any measurable change to the human, it must happen regularly, over an extended period of time.”

“Oh, my god,” said Sam.

Dean grinned. “That’s right, Sammy – blowjobs give me superpowers!”

“That is not entirely accurate,” said Cas, still frowning.

“Superpowers,” Dean repeated. “Advanced healing, better hearing, better vision. If I had claws, I’d be Wolverine.”

“I just…” said Sam, faintly. “I can’t un-know this, Dean!”

“You kept poking at it,” his brother replied, entirely unsympathetic.

“I thought you were in trouble!” Sam protested. “When I… with Ruby, I was not in a good place, and if there was even a chance that you…”

“Hey,” said Dean, softly, putting a hand on his brother’s shoulder and shaking him gently. “First, worrying about you is my job, so you don’t get to ruin it by worrying about me. And second, me and Cas… we’ve got an agreement, now – no more doing stupid stuff on our own. If we’re going to do something stupid, we do it _together_.”

Sam managed a laugh. “That sounds about right. Now, if you’ll both excuse me, I need to go bleach my brain.”

Cas looked faintly alarmed. “Sam, that sounds like a very dangerous—” He broke off, frowning. “That’s a metaphor, isn’t it?”

“Yeah,” said Sam. “But one more question – is this going to get any worse?”

“It’s not a disease, Sammy,” protested Dean, but Cas looked thoughtful.

“Dean’s abilities have been more-or-less consistent for almost a year, so it is unlikely they will increase. However, it is possible they may be permanent, after so long, even if he were no longer exposed to the source.”

“Yeah, well, we’re not going to find out,” said Dean, fiercely.

Sam thought that was sweet – for about three seconds, before he remembered what the ‘source’ was.

“Okay!” he said, quickly. “That’s enough of that. For future reference, Cas, you should just tell me these things directly – unless it’s about your sex life, which I never want to hear about ever again.”

“We understand,” said Cas, while Dean just snickered, until a timer went off in the kitchen.

“Crap, dinner,” said Dean, and raced out.

There was a beat of silence, then Cas said, “There is one other matter.”

“Oh?” Sam asked, warily.

“I cannot be sure at this time,” the angel said, slowly. “But I believe that my grace will also cause Dean to live longer.”

“What, like you?”

Cas shook his head. “No. He would still live a normal human lifespan, no more than a century or so. But you may not.”

“Oh,” said Sam, again. “You think Dean is going to outlive me, now.”

“Yes, and it will be very difficult for him.”

“Well, with any luck, I’ll be able to give him a long time to get used to the idea. And besides,” he added, clapping Cas on the shoulder, “he’ll have you.”

“For all eternity, if he will have me,” said Cas, seriously, just as Dean came back in.

“Dude, c’mon, no chick flick crap,” said Dean, but he was smiling. “Grow a pair, already.”

The angel smirked. “As you have personally seen my—”

“Whoa, okay, _no_!” said Sam, raising both hands. “No more sex talk. Ever. For my entire life. Understood?”

“I can make no such promise,” said Cas. “But I will try. As will Dean.”

“I – Okay,” his brother agreed.

Sam laughed. “Okay. Wait, hey, Dean?”

His brother, already heading back to the kitchen, half-turned. “Yeah?”

“Can you see Cas’s wings?”

“Yeah,” Dean repeated, more a breath than a word, and more full of love and awe than Sam had ever heard from him. “Yeah, I can.”

“Good,” said Sam, and left before he could ask anything else.

THE END


End file.
